Cellulose ester.



. film orsheet. Furthermore,

, with other solvents, or to addto it,

solution of cellulose acetate in methyl clilorment in Cellulose Esters,

about 129 centigrade,

films, filaments and the like.

' [UNITED STATES "PATENT OFFICE x HARRY S. MORK, OF BOSTON, MASSACHUSETTS, ASSIGNOR T0 CHEMICAL PRODUCTS COMIEAN Y, OF BOSTON, MASSACHUSETTS, A.

CORPORATION or MAINE.-

CELLULOSE ESTER. 1

1,039,782. Hopi-swing.

I Specification of Letters Patent. Application filed March 17, 1910. Serial No. 549,935.

Patented Oct. 1, 1912.

To allwuhom it may conccrnr Be it known that I, HARRY S. Mon-K, of Boston, in the county of Suffolk and State of Massachusetts, have invented an Improveof which the following is a specification.

This invention relates to improvements in cellulose esters of the fatty acids, as cellulose acetate, and particularly to the dissolving or gelatinizlng of these esters by new solvents, whereby commercially useful films, filaments, and the like may be prepared.

In the manufacture of films,'filaments and the lilte from cellulose esters, and particularly ,cellulose acetate, it is desirable to use asa solvent, or as one component of a solvent mixture, a neutral liquid having a boiling point'somewhat higher than that. of

water, so that the evaporation of the solvent shall not be too rapid, and so that moisture may be expelled during the formation of the a for the production of filaments or artifici'al silk or horsehair from solutions: of cellulose acetate, by injecting such a solution into acoagulating liquid, the 'use of a solvent with a boiling point greater than thatrof -water is sometimes desirable, for it will permit the use of a coagulating liquid of relatively lower boiling point to be used, a number of which liquids are commercially available. The solvent of a boiling point greater than that of water can easily be recovered from the co-.

agulating bath by a simple fractional distillat-ion. A I

I have discovered that the methyl-ester of.

chloracetic acid, a neutral liquid boiling at is a very excellent solvent of cellulose acetate, and fromsolutions, of cellulose acetate in methyl chloracetate can be prepared commercially useful As, for, ex-

of cellulose gallon of methyl chloracetate,

ample, bye.

issolving one pound films ncely, and leaves,

transparent films or sheets." v I 1 It is not necessary to .use methl chloracetate as a solvent by itself, aspurposes it may be advantageous :acetate and another solvent. 3. A composition of matter conslsting of or' many to mix it or to the.

I acetate,- with or without other solvents,.an

alcohol which will increase the dissolving power of the solution although alone not a solvent for the cellulose a cetate;or even to add to the solution offcellulose acetate in methyl chloracetate liquidswhich are in no sense solvents of cellulose acetate.

If it is desired that a solution of cellulose.

acetate be prepared that will evaporate quicker than the solution of cellulose acetate in methyl chloracetate alone, a more rapidly evaporating solvent, such as acetone or chloroform, may be added to methyl chloracetate' to produce a mixed solvent, the amount ad ded,depending upon the increased rate of evaporation desired. Or, for example, in. case it should be desiredto increase the rate, of coagulation of a solution of cellulose acetate in methyl chloracetate, when injected into a coagulating bath consisting, advantage to add to the solution a limited amount of a monohydric alcohol of the parafiin series of a boiling point below 80 (1, which alone is a non-solvent of the cellulose acetate but which has the effect of adding to the dissolving power of the solution.

Ifit is desired to produce a dilute solution of cellulose acetate in methyl chloracetate, a limited amount of a non-solvent, such as benzol or carbon'tetrachlorid, may be added to a more concentrated solution of cellulose acetate in methyl chloracetate than the-final solution desired.

When using the other solvents,as acetone, or chloroform, or when using the alcohols or absolute non-solvents with or without the other solvents, it is not necessary that the ingredients be order.

; I claim: i i I 1. A compositionv of matter consisting of cellulose acetate, dissolvedlin methyl chloracetate.

2. A composition of matter eon sisting of cellulose. acetate, dissolved in methyl chlor- .cellulose acetate, dissolved, in methyl chloraceta-te and a monohydric alcohol of the paraffin series boiling-below 80 4., A composition of matter consisting of cellulose acetate, dissolved in methyl chlormixed in any particular say, of an alcohol, it would be of V Q 1,039,7sa

ing of methyl chloracetate and another solvent and a monohyclric alcohol of the paraffin series boiling below 80 C.

In testimony whereof, I have signed my 15 name to this specification, in the presence of two subscribing witnesses.

HARRY S. MORK.

Witnesses B. J. Noyes, H. B. DAVIS. 

